6-23
Catalyst 3550 Multilayer Switch Software Configuration Guide
78-11194-03
Chapter6 Administering the Swi tc h Controlling Switch Access with RADIUS
This example shows how to configure host1 as the RADIUS server and to use the default ports for both
authentication and accounting:
Switch(config)# radius-server host host1
Note You also need to configure some settings on the RADIUS server. These settings include the I P
address of the switch and the key string to be shared by b ot h th e serve r an d th e switc h. For m or e
information, refer to the RADIUS server documentation.
Configuring RADIUS Login Authentication
To configure AAA authentication, you define a named list of authentication methods and then apply that
list to various interfaces. The method list defines the types of authentication to be performed and the
sequence in which they are performed; it must be applied to a speci fic interface before any of the defined
authentication methods are performed. The only exception is the default method list (which, by
coincidence, is named default). The default method list is automatically applied to all interfaces except
those that have a named method list explicitly defined.
A method list describes the sequence and authentication methods to be queried to authenticate a user.
You can designate one or more security protocols to be used for authentication, thus ensuring a backup
system for authentication in case the initial method fails. The software uses the first method listed to
authenticate users; if that method fails to respond, the software selects the next authentication method
in the method list. This process continues until there is successful communication with a listed
authentication method or until all defined methods are exhausted. If authe ntica ti on fai ls at an y poi nt in
this cycle—meaning that the security server or loca l use rnam e dat abas e re spon ds by de nying the u se r
access—the authentication process stops, and no other authentication methods are attempted.
Beginning in privileged EXEC mode, follow these steps to configure login authentication. This
procedure is required.
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 aaa new-model Enable AAA.